jdk1.8中stream用法

public static void main(String[] args) {
//new一個list，給list添加三組值。
List list = new ArrayList<>();
VehicleInfo vehicleInfo = new VehicleInfo();
vehicleInfo.setSysOrgId(100);
vehicleInfo.setTerminalType(“2”);
list.add(vehicleInfo);
VehicleInfo vehicleInfo1 = new VehicleInfo();
vehicleInfo1.setSysOrgId(100);
vehicleInfo1.setTerminalType(“3”);
list.add(vehicleInfo);
VehicleInfo vehicleInfo2 = new VehicleInfo();
vehicleInfo2.setSysOrgId(101);
vehicleInfo2.setTerminalType(“2”);
list.add(vehicleInfo2);
//查詢出sysOrgId是100的集合。
List vehicleInfos = list.stream().filter(a ->100a.getSysOrgId()).collect(Collectors.toList());
//查詢出sysOrgId是100的集合的第一個，返回值是Optional類型
Optional vehicleInfo3 = list.stream().filter(a ->100a.getSysOrgId()).findFirst();
//判斷vehicleInfo3是不是空的
if (vehicleInfo3.isPresent()) {
//把optional的值給實體類
VehicleInfo vehicleInfo4 = vehicleInfo3.get();
System.out.println(vehicleInfo4);
}
System.out.println(vehicleInfos);
}